Molecular and biochemical protective roles of sodium nitroprusside in tomato (Lycopersicon esculentum Mill.) under salt stress

Salinity stresses act as inhibitor factors of plant growth. They can change the physiological characteristics and limit the production of crops. Sodium nitroprusside (SNP) is a stable free radical which is used as a signaling molecule in plants and participates in various plants’ physiological, biochemical, and molecular processes and also in plants’ responses to environmental stresses. We investigated the effect of SNP on physiological parameters such as photosynthetic and non-enzymatic pigments, biochemical parameters like APX and SOD enzymes and HKT1.2 and SLWRKY 8 genes expression as a molecular section on tomato under salt stress. In this study, SNP was used as nitric oxide (NO) donor. Tomato seedling roots were subjected to various levels of salinity including 0, 40, 80, and 120 mM and SNP (0, 50 and 100 mM) for 20 days. The SNP had protective effects on photosynthetic parameters by increase in non-enzymatic and enzymatic antioxidants. It had also reducing and increasing effect on HKT1.2 and SLWRKY 8 gene expressions, respectively.